The present invention deals with fluid-controlled switches, some of their accessories, their combination with electrically-controlled switches to produce conglomerate switches with excellent characteristics, and switching networks containing the switches. There are two main areas in which electrically-controlled electrical relays are extensively used. The first is in telephone switching networks, where ferreeds and remreeds have been extensively used. These devices are bulky and must be manufactured and checked individually. Also their operation necessitates electromagnetic fields being in proximity to transmission lines. The remreeds also carry fairly low power. Therefore, it is one purpose of the present invention to show how relays of reduced bulk, excellent isolation, low closed-circuit impedance, negligible open-circuit conductance and capacitance, and good reliability can be manufactured by mass production techniques. These relays can be easily integrated into a present telephone switching network, since the range of operating voltages from a few volts up to hundreds of volts includes the voltage currently used in such networks. The subject switches of the current invention have a further advantage over remreeds in that they carry status signals in their reset state to determine whether a particular line is currently in use.
A second use of electrically-controlled electrical relays is in the area of controlling high power or high voltage circuits. Solid-state relays for such applications are now available with fair isolation between controlling and controlled circuits for about $5.00 apiece. Therefore, it is a further purpose of the present invention to provide relays capable of performing high voltage and high power switching with a wide range of control voltages, low resistance heating, and excellent electrical isolation between controlling and controlled circuits. Further, the relays of the present invention are not bulky and can be manufactured cheaply by mass production techniques.
Some other purposes of the present invention are to provide:
(1) an efficient fluid amplifier for hydraulic systems with said amplifier having positive shut-off, high power capacity, and low switching power consumption; PA1 (2) a compact and efficient fluid to electric signal transducer; PA1 (3) a compact but powerful electric to fluid signal transducer in the form of a conglomerate switch consisting of an electrically-controlled fluid switch connected to a second switch, which is a fluid amplifier switch acting as a follower; PA1 (4) a switching system which indicates status at all times by a separate set of signals, and two methods of producing destructive mark operation; PA1 (5) a power transducer taking heat as an input and producing fluid flow power as an output; PA1 (6) a three port fluid system inhibiting flow between two ports but allowing almost free flow between any other pair of ports.